Trap-door lifter.



No. 739%,,3M1L. I PMLFENTED SEPT, 22, 1903.

' F. FOUNTAIN.

v TRAP DOOR-LIFTER. APPLIOATION FILED DEC. 18, 1902.

NO MODEL.

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WITNESSES: %M

ATTORNEY Patented September 22, 1903.

PATENT OFFICE.

FRANK FOUNTAIN, OF .OHARLEVOIX, MICHIGAN.

. TRAP-DOOR LIFTER.

SPECIFICATION forming'part of Letters Patent N0. 739,301, dated September 22, 1903. Application filed December 18, 1902. Serial No. 135.816. (No model.) Y

To all whom it may concern:

Be it known that I, FRANK FOUNTAIN, a citi- Zen of the United States, residing at Charlevoix, in the county of Charlevoix and State of Michigan, have invented certain new and useful Improvements in Trap-Door Lifters; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention is a trap-door lifter.

. It comprises an adjustable device adaptable to any trap-door which operates below the door to automatically lift and hold it upright when released by a simple latch.

Similar numerals of reference refer to similar parts in the accompanying drawings, in which Figure 1 is an elevation, broken away in parts, of a trap-door operated-by my device. Fig. 2 is a section on the line w w of Fig. 1 with parts broken away. Fig. 3 is a part sectional side view of the lifter detached, and Fig. 4 is a bottom view of the lifter.

The construction and operation of the device are as follows: A bent lever 1 is pivotally supported near its middle below the hinged edge of the door 2. The lifting-arm 1 extends under the door and carries a roller 3 near its front end adapt= ed to roll on the under face of the door as it lifts. The opposite or weight arm 1 of the lever carries'an adjustable counterweight 4, This weight may be secured in different positions to balance doors of different sizes.

The lifting-lever may be supported in any suitable manner; but I prefer to support it by a bracket 5, secured to the door-frame 2. This bracket has a vertical slot totake the pivoted lug 1 of the lever.

The roller 3 is carried at the outer end of a double bar 6, which is secured to the end of the arm 1 by through-bolts 7. Slotted holes 1" permit the bar 6 and roller 3 to be adjusted lengthwise to suit doors of different widths. i

To hold the lifter down when the door is closed, as shown by dotted lines in Fig. 2, I provide a plate 8, having a slot 8 to engage the spring-actuated latch 9, secured to the door-frame. The plate 8 has on each side a lifting-arm is free from the door when the latter is closed, the plate 8 can be so adjusted upon the lifting-arm that the roller will not lift up on the door, but will be held a short distance below it when the slot 8 of the plate 8 engages the latch 9, thereby permitting the weight of the door to rest on the frame 2 instead of on the latch and bringing the upper surface of the door flush with the floor-line. The roller is fixed on a spindle 10, turning in holes in the double bar. The ends of the spindle project beyond the sides of the bar,

and a pair of brackets 11 on the under side of the door 2, carrying depending slotted flanges 11, receive the ends of the spindle lO as the door lifts. By this means the door is held upright when open and locked against any tendency to fallover backward.

The latch 9 isoperated by a cord-12, passing over guide-pulleys 13 within the wall and.

winding on a shaft 14:, projecting into the room at a convenient height near the door and provided with a knob 14 for its rotation. A turn of the knob withdraws the latch and releases the lifter, which carries the door to an upright position and holds 'itthere.

By the means above described I have constructed a lifter adjustable totrap-doors of different sizes which when released operates easily to gently lift the door and hold it upright. The device is capable of being so accurately balanced as to operate with out noise or jar, enabling the door to be closed by slight pressure from above. I

What I claim as my invention, and desire to secure by.Lette'rsPatent, isg j 1. A trap-door lifter comprising in combination a vertically-movable lever pivotally mounted below the hingededge of the door, having alifting-arm extending forwardly under the door and a rearwardly-extending weight-arm; a roller carried by the liftingarm and adapted to roll on the under side of the door; and means for locking and releasing the lever; and a bracket securedto the under side of the door adapted to engage a projection from the lifting-arm to hold the door upright when open 2. A trap-door lifter comprising in c01nbination a verticallyunovable lever pivotally mounted below the hinged edge of the door, having a lifting-arm extending forwardly under the door and a rearwardly extending weight-arm; a weight adjustable lengthwise the weight-arm; a roller carried by the lifting-arm, adjustable lengthwise thereof and adapted to roll 011 the under side of the door; a spindle in the roller having its ends projecting beyond the sides of the lifting-arm; brackets secured to the under side of the door adapted to engage the ends of the spindle as the door opens to hold the door upright; a plate carried at the end of the lifting-arm and having a slot; means for adjusting the plate vertically 0n the end of the lifting-arm; a spring-actuated latch secured to the doorframe and adapted to engage the slotted plate on the lifting-arm.

3. In combination with a trap-door lifter of the class described having a lever pivotally supported below the edge of the door and having a weight-arm and a lifting-arm of the class described; a bracket carried by the door and adapted to engage a projection from the lifting-arm and to hold the door upright When open and to be out of engagement with said projection when the door is closed.

4. In a trap-door lifter, having a lifting-arm of the class described; a plate secured to the free end of the lifting-arm, said plate being formed with a slot adapting it to engage a latch; and means for adjusting said plate vertically transverse the lifting-arm, for the purpose set forth.

5. In combination with a trap-door lifter having a lifting-arm of the class described a pin extending beyond the sides of the liftingarm and a pair of brackets secured to the under side of the door having depending flanges with slots therein adapted to engage the ends of said pin as the door opens for the purpose set forth.

6'. In a trap-door lifter having a liftingarm of the class described; a plate having a slot adapting it to engage a latch, secured to the end of the lifting arm; said plate being formed with a pair of baclnvardly-extending flanges, one on each side of the lifting-arm, and having a pair of set-screws one threaded i through each flange and bearing against the lifting-arm securing the plate thereto and permitting its adjustment thereon.

In testimony whereof I aflix my signature in presence of two witnesses.

FRANK FOUNTAIN.

Witnesses:

HORACE S. I'IARSHA, A. H. BUTTARS. 

